I Hid a Secret Message in a Cat Photo and Nobody Noticed for Six Months

Note: dev.to modifies the image, the original image with the secret is the original post 🤘 I found a steganography challenge in a CTF last year that had me staring at a picture of a cat for two hours. The image looked completely normal; 800x600 pixels of an orange tabby sitting on a keyboard. No metadata anomalies, no appended ZIP files, no obvious artifacts. The flag was hiding in the least significant bits of the blue channel. Once I extracted it, the message was 43 characters long. The cat h